FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
Games and Video Games
Before discussing game design, we have to establish what games are and how they work. You might think that everybody knows what a game is, but there are so many kinds of games in the world that it's best not to make assumptions based on personal experience alone. We'll start by identifying the essential elements that a game must have, and then define what a game is based on those elements. Then we'll go on to discuss what computers bring to gaming and how video games are different from conventional games. Finally, we'll look at the specific ways in which video games entertain people and note some other enjoyable features of video games that you must learn how to design.
Work consists of whatever a body is obliged to do, and. . . Play consists of whatever a body is not obliged to do.
—Mark Twain, The Adventures of Tom Sawyer
Games arise from the human desire for play and from our capacity to pretend. Play is a wide category of nonessential, and usually recreational, human activities that are often socially significant as well. Pretending is the mental ability to establish a notional reality that the pretender knows is different from the real world and that the pretender can create, abandon, or change at will. Playing and pretending are essential elements of playing games. Both have been studied extensively as cultural and psychological phenomena.